Loading device for containers or similar

ABSTRACT

A loading device for containers (C) comprises a pair of loading units ( 2 ), each having a telescopic column ( 4 ) supported on a bracket ( 3 ) so as to be swivelled about a common swivel axis (I). The telescopic column consists of a lower portion ( 9 ), an upper portion ( 11 ) and a column cylinder ( 17 ) moving the upper portion ( 11 ) with respect to the lower portion ( 9 ). Actuating cylinders ( 5 ) are connected to the lower portion ( 9 ) on both sides, and the upper portion ( 11 ) accommodates an extension arm ( 14 ) which can be swivelled about a swivel axis (III) parallel to the swivel axis (I) of the telescopic column. To expand the loading possibilities, the upper portion ( 11 ) carries a column head ( 12 ) which forms a slot-shaped swivel guide ( 18 ) with cam tracks ( 19 ) limiting the swivelling of the extension arm ( 14 ). The extension arm ( 14 ) has guide members ( 20 ) and is pivotally connected with a sliding piece ( 13 ) movably seated inside the upper portion ( 11 ) which opens towards the swivel guide ( 18 ), where a constriction ( 21 ) is provided between the cam tracks ( 19 ), so that the guide members ( 20 ) of the extension arm ( 14 ) aligned in a position stretched with respect to the telescopic column ( 4 ) simultaneously contact both cam tracks ( 19 ), and on the side of the upper portion the column cylinder ( 17 ) acts on the sliding piece ( 13 ) which can be moved upwards along a path limited by a stop.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a loading device for containers or the like,comprising a pair of loading units to be mounted on an undercarriage,which each have a telescopic column supported on a bracket so as to beswivelled about a common swivel axis extending in the longitudinalcenter of the undercarriage, which telescopic column consists of a lowerportion pivotally mounted on the bracket, an upper portion movablyguided in the lower portion, and a column cylinder moving the upperportion with respect to the lower portion, where actuating cylinders acton the lower portion on both sides, and the upper portion accommodatesan extension arm which can be swivelled to both sides about a swivelaxis parallel to the swivel axis of the telescopic column and has anabutment for connection of a load lifting means.

2. Description of the Prior Art

Such loading device is known for instance from EP 0 705 179 A, and it isalso well-tried because of its relatively simple and compact design, itssturdiness and its small space requirement as compared to the loadingarea. However, in the known loading device the extension arm of thetelescopic columns can only be swivelled from one side to the other freefrom load, so that for a loading operation where a container must bemoved from one side of the undercarriage to the other the container mustbe deposited on the undercarriage to relieve and swivel the extensionarm, which is time-consuming and complicated. And under load, theextension arm can only be used in its stop-limited lateral swivelposition, which involves a certain restriction of the loadingpossibilities.

SUMMARY OF THE INVENTION

It is therefore the object underlying the invention to create a loadingdevice as described above, which allows to swivel containers throughfrom one side of the undercarriage to the other, and by swivelling theextension arms even under load involves an expansion of the loading areaand the prerequisite for stacking the containers.

This object is solved by the invention in that the upper portion of thetelescopic column carries a column head which forms a slot-shaped swivelguide with cam tracks limiting the swivelling range on both sides forthe extension arm, that the extension arm has guide members associatedto the cam tracks and is pivotally connected with a sliding piecemovably seated inside the upper portion which opens towards the swivelguide of the column head, where in the vicinity of the orifice aconstriction is provided between the cam tracks, so that the guidemembers of the extension arm aligned in a position stretched withrespect to the telescopic column simultaneously contact both cam tracks,and that on the side of the upper portion the column cylinder acts onthe sliding piece which can be moved upwards in a stop-limited way.

The actuating cylinders can swivel the telescopic column towards bothsides in the usual way about the common swivel axis extending in thelongitudinal center of the undercarriage, where independent of therespective swivel position the column cylinder inside the telescopiccolumn remains actuatable in both directions. When the column cylinderhas been retracted to its starting position, it has on the one handbrought the upper portion to its lowermost position and on the otherhand retracted the extension arm into the upper portion via the slidingpiece, so that the extension arm moving together with the guide membersalong the cam tracks is in alignment with the telescopic column. Whenthe column cylinder is extended, the sliding piece is moved upwards, sothat corresponding to the swivel position of the telescopic column theextension arm moving upwards swivels towards the one or the other sidecorresponding to the cam track guiding the guide pieces and swings tothe corresponding side. When the lateral swivel limit has been reachedbecause the sliding piece strikes against the limit stop, the upperportion is lifted out of its basic position when the column cylinder isextended further via the sliding piece, and can be moved upwards withrespect to the lower portion up to a desired extended position. Alongwith the possibilities for swivelling the telescopic column to the sidethere are thus obtained the different loading possibilities, where themovements of the telescopic column and also of the extension arm caneasily be effected even under load due to the correspondingly stronglydimensioned column cylinder. It is thus also easily possible to forinstance pick up a container standing on the one side of theundercarriage, then lift it up and swivel it to the other side of theundercarriage and let it down again and deposit it, or to bring acontainer from the loading surface of an adjacent vehicle to theopposite side of the undercarriage, and the like.

To ensure that the extension arm can be swivelled properly by means ofthe column cylinder, the upper portion of the telescopic column must befirmly supported with respect to the lower portion, which support isprovided from the start in the retracted telescope position. To be ableto perform a swivel movement of the extension arm also in variousextended positions of the telescopic column, the lower portion of thetelescopic column is equipped with a locking device for selectivelylocking the upper portion in one or more extended positions, so that theswivel height of the extension arm and thus also the loading height ofthe containers can be chosen as desired. With such a predeterminableworking height of the telescopic column and of the extension arm it isnow also possible to lift containers to such an extent and swivel themto the side that a container can be deposited on a ramp of acorresponding height, a loading surface of a vehicle, but also forstacking purposes on a container already deposited there, or can bepicked up from a storage area of a corresponding height.

As guide members for the extension arm there might be provided suitablesliding surfaces or the like, but as guide member the extension armexpediently has a guide roller rotatably mounted about an axis ofrotation parallel to the swivel axis of the extension arm, which guideroller has a diameter adapted to the constriction between the camtracks. Such guide roller provides for a smooth, low-noise relativemovement between extension arm and column head and also ensures an exactguidance of the extension arm when swivelling the same and when aligningthe same in the vicinity of the constriction.

To prevent that in the case of a swivel movement of the telescopiccolumn during the actuation of the column cylinder an undesired reversalof the extension arm from one swivel side to the other takes place,which in the case of a higher load might lead to a damage of the loadingdevice, the extension arm movement along a corresponding connecting linkguide might be forcibly controlled, which would, however, involve therisk of jams and the like. It would therefore be more expedient to equipthe extension arm with a locking bar associated to a locking projectionof the column head as a protection against reversal, which locking barstrikes against the locking projection when the extension arm swivelsupwards before reaching the stretched position, and prevents a furthermovement. Only when a deliberate unlocking is effected can the lock beremoved and the reversal be effected.

When in accordance with a further aspect of the invention the telescopiccolumn together with the actuating cylinders is mounted on a carriage ofthe bracket which is movable transverse to the swivel axis, the loadingarea can be expanded further to the side due to this transverseadjustability, and there is an increase in the possible uses of theloading device.

It is also expedient when in accordance with the invention the brackethas an upper structure to be folded down about a lying transverse axis,which upper structure carries the telescopic column together with theactuating cylinders, so that the parts of the loading device usuallyprotruding above the driver's cab can be folded down for a railwaytransport or the like in the unloaded condition to reduce the transportheight.

BRIEF DESCRIPTION OF THE DRAWING

In the drawing, the subject-matter of the invention is illustrated byway of example, wherein:

FIG. 1 represents a vehicle with an inventive loading device in variousloading positions by means of a rear view,

FIG. 2 represents a vehicle with an inventive loading device in a sideview,

FIG. 3 represents a telescopic column of the loading device in a partlysectional rear view on an enlarged scale,

FIGS. 4 and 5 represent the locking device of the telescopic column in atop view and in a cross-section along line V—V of FIG. 4, and

FIGS. 6 and 7 represent the column head of the telescopic column in arear view and in a cross-section along line VII—VII of FIG. 6, likewiseon an enlarged scale.

DESCRIPTION OF THE PREFERRED EMBODIMENT

On an undercarriage 1, for instance a truck, there is mounted a loadingdevice for containers C comprising two loading units 2, where eachloading unit 2 consists of a bracket 3, a telescopic column 4 supportedon the bracket 3 so as to be swivelled about a swivel axis I extendingin the longitudinal center of the undercarriage 1, which telescopiccolumn has actuating cylinders 5 acting on both sides, and of supportinglegs 6 to be swivelled down towards both sides, which for the sake ofclarity are only indicated in FIG. 2. As is represented in FIG. 1, thebracket 3 can have a carriage 7 movable transverse to the swivel axis Ifor accommodating the telescopic column 4 and the actuating cylinders 5,so as to be able to expand the loading area by means of a lateraldisplacement of the loading units 2. As is shown in FIG. 2, it is alsopossible to equip the brackets 3 with an upper structure 8 to be foldeddown about a lying transverse axis 11 for accommodating the telescopiccolumn 4 and the actuating cylinders 5, in order to fold down theprotruding parts (represented in broken lines) to reduce the transportheight of the unloaded vehicle. The upper structure possibly can, in amanner not represented in detail, also accommodate the supporting legs 6in addition to the telescopic column, so that the entire loading unitscan be folded down.

As can be taken in particular from FIG. 3, the telescopic column 4consists of a lower portion 9 pivotally mounted on the bracket 3, onwhich act the actuating cylinders 3 via suitable connecting plates 10,of an upper portion 11 movably guided in the lower portion 9, which atits free end carries a column head 12, of a sliding piece 13 movablyinserted inside the upper portion 11, on which an extension arm 14 withan abutment 15 is pivotally mounted about a swivel axis III parallel tothe swivel axis I for connection of a load lifting means 16, forinstance a carrying gear for picking up a container, and of a columncylinder 17 which is supported on the one hand on the lower portion 9 oron the swivel axis I and which on the other hand acts on the slidingpiece 13, which can be moved upwards from the upper portion 11 into thecolumn head 12 up to a limit stop not represented in detail. The columnhead 12 forms a slot-shaped swivel guide 18 for the extension arm 14,where the swivelling range is limited by lateral cam tracks 19. Theextension arm 14 is equipped with guide members associated to the camtracks 19, for instance with guide rollers 20 rotatable about an axis ofrotation IV parallel to the swivel axis III, which guide rollers 20 havebeen adapted in their diameter to the constriction 21 between the twocam tracks 19 provided in the vicinity of the orifice of the upperportion 11 towards the swivel guide 18 of the column head 12, so that inthe case of a retraction of the sliding piece 13 the extension arm 14can be aligned in a position stretched with respect to the telescopiccolumn 4.

The column head 12 forms a central locking projection 22 to which thereis associated a locking bar 23 of the extension arm 14 as a protectionagainst reversal, where the locking bar 23 for instance constitutes adouble-acting locking cylinder 24 for selectively locking or unlocking.

At the lower portion 9 of the telescopic column 4 a locking device 25 isprovided, which consists of two locking combs 26, 27 spaced from eachother in longitudinal direction of the column and of an actuatingcylinder 29 pivotally mounted on the two locking combs via swivellinglevers 28, so that by actuating the actuating cylinder 29 both lockingcombs 26, 27 are disengaged or alternately the one or the other can beengaged in its locking position. In the locking positions, the lockingcombs protrude through corresponding openings into the lower portion 9and engage below the upper portion 11 in a middle or upper extendedposition, where by means of a positive connection between the lockingcombs and the upper portion or a correspondingly weak dimensioning ofthe actuating cylinder 29 unlocking is not possible when the upperportion is loaded.

The inventive loading units 2 not only provide for an extension orretraction or a swivel movement of the telescopic column 4, but also fora swivel movement of the extension arm 14 and also a reversal of thisextension arm 14 under load, so that there is obtained a wide range ofapplications with all kinds of loading possibilities. As is indicated inFIG. 1, a container C can for instance be picked up from an elevatedloading surface L or be deposited on such elevated loading surface L, itis possible to transfer the container C from one side of the vehicle tothe other and deposit the container on the ground, but also to stack twocontainers C on top of each other. In addition, the loading units 2 canbe brought into a transport position, which, as is likewise indicated inFIG. 1, finds room inside the outer contour of a loaded container C.

The lateral swivel movements of the telescopic column 4 are performedvia the actuating cylinders 5, where independent of the swivel positionsthe inner column cylinder 17 can be actuated for swivelling theextension arm 14 or for extending and retracting the upper portion 11.For instance, when the column cylinder 17 in the position represented inFIG. 3, which corresponds to a first extended position of the upperportion with a locking by the lower locking comb 26, is acted upon inextension direction, the sliding piece 13 is moved upwards and theextension arm 14 is thus swivelled out to the side while the guiderollers 20 roll along the cam track 19, where by swivelling thetelescopic column 4 to the side the extension width can be increased.When the column cylinder 17 is retracted, the extension arm 14 isswivelled upwards in direction of the stretched position due to thelocking of the upper portion 11, until the locking bar 23 rests againstthe locking projection 22, which prevents an undesired reversal of theextension arm 14. When the locking bars 23 are unlocked, a furtherretraction of the column cylinder 17 can retract the sliding piece 13into the upper portion 11 up to the stretched position of the extensionarm 14, where the guide rollers 20 now simultaneously rest against bothcam tracks 19 in the vicinity of the constriction 21 and stabilize thecentral position of the extension arm 14. When during this retractionoperation or upon reaching the stretched position the telescopic column4 has swivelled from the one side to the other, the extension arm 14with its guide rollers 20 can swivel to the other side along the otherguideway 19 during an upward movement of the sliding piece 13 and takealong the load picked up during its swivel movement. When the reversalis terminated and the sliding piece 13 has reached its limit stop duringthe extension of the column cylinder 17, the upper portion 11 isextended during a further extension of the column cylinder 17 togetherwith the sliding piece 13, which leads to an elevation of the telescopiccolumn 14. As soon as the upper portion relieves the locking device 25,the locking comb 26 can be withdrawn, and possibly after a correspondingextension of the upper portion 11 the higher located locking comb 27 canbe inserted, so that now in a further extended position, for instance ina stacked position, the extension arm 14 can again be swivelled byretracting the column cylinder 17.

What is claimed is:
 1. A loading device for containers comprising a pairof loading units to be mounted on an undercarriage, which each have atelescopic column supported on a bracket so as to be swivelled about acommon swivel axis extending in the longitudinal center of theundercarriage, which telescopic column consists of a lower portionpivotally mounted on the bracket, an upper portion movably guided in thelower portion, and a column cylinder moving the upper portion withrespect to the lower portion, where actuating cylinders are connected tothe lower portion on both sides, and the upper portion accommodates anextension arm which can be swivelled to both sides about a swivel axisparallel to the swivel axis of the telescopic column and has an abutmentfor connection of a load lifting means, characterized in that the upperportion carries a column head which forms a slot-shaped swivel guidewith cam tracks limiting the swivelling of the extension arm, that theextension arm has guide members associated with the cam tracks and ispivotally connected with a sliding piece movably seated inside the upperportion which has an open end facing the swivel guide of the columnhead, where in the vicinity of the open end a constriction is providedbetween the cam tracks so that the guide members of the extension armaligned in a position stretched with respect to the telescopic columnsimultaneously contact both cam tracks, and that on the side of theupper portion the column cylinder acts on the sliding piece which can bemoved upwards along a path limited by a stop.
 2. The loading device asclaimed in claim 1, characterized in that the lower portion of thetelescopic column is equipped with a locking device (25) for selectivelylocking the upper portion (11) in one or more extended positions.
 3. Theloading device as claimed in claim 1, characterized in that the eachguide member of the extension arm is a guide roller rotatably mountedabout an axis of rotation parallel to the swivel axis of the extensionarm, which guide roller has a diameter conforming to the constrictionbetween the cam tracks.
 4. The loading device as claimed in claim 1,characterized in that the extension arm is equipped with a locking bararranged to engage a locking projection protection of the column head asa protection against reversal.
 5. The loading device as claimed in claim1, characterized in that the telescopic column together with theactuating cylinders are mounted on a carriage of the bracket thecarriage being movable transverse to the swivel axis.
 6. The loadingdevice as claimed in claim 1, characterized in that the bracket has anupper structure downwardly pivoted about a lying transverse axis, whichcarries the telescopic column together with the actuating cylinders.